It is common practice to provide, for example in supermarkets and other retail outlets, dispensers for dispensing pre-formed bags (e.g. plastic bags) from a stack of such bags.
A simple known system hangs a stack of T-shirt type handle bags from two substantially horizontal support rods. For example, U.S. Reissue Pat. No. 33,264 (Baxley et al; Jul. 17, 1990), the disclosure of which is incorporated herein by reference, describes an arrangement (illustrated in FIG. 1 of the accompanying drawings) in which each bag is provided with two support rod receiving apertures in its handle portions 1, such that the apertures pass through the stack of bags 2 and receive the support rods 3, 4. The stack of bags 2 is also provided with a bonded block ("header") of detachable mounting tabs which extends from a central area of a mouth portion of a bag and is provided with a mounting aperture 5. The dispenser takes the form of a metal frame having two rods projecting forwards to provide the support rods 3, 4, and having a shorter hook element 6 projecting between the support rods 2,3 to receive in use the mounting aperture 5 of the bonded block of mounting tabs. The central bonded block of detachable mounting tabs can be omitted (FIG. 5 of U.S. Pat. No. Re. 33,264). The support rod receiving apertures can be formed by a generally C-shaped cut in each handle portion 1, which defines a flap lying across the aperture of the respective handle of the respective bag. Before hanging the stack of bags on the dispenser the flaps substantially close the apertures of the stack. On engaging the stack of bags on the support rods the support rods push the flaps down and thereby open the support rod receiving apertures (FIGS. 3 and 8 of U.S. Pat. No. Re. 33,264). The flaps are permanently heat sealed together, as indicated by numeral 44 in FIG. 3 of U.S. Pat. No. Re. 33,264 and the associated description.
The bags of the stack 2 can be adhesively bonded together via spots or regions of adhesion, whereby the act of drawing one bag forward along the support rods 3, 4 will cause the next following bag to partially open (FIG. 2 of U.S. Pat. No. Re. 33,264). After the first bag has been loaded it is lifted forwardly off the support rods 3, 4 and the adhesive bond broken to detach the bag from the dispenser. The flaps are broken away and the broken-off flaps are left on the dispenser, still heat-sealed to the flaps of the next bag of the stack.
In another form of such a system, U.S. Pat. No. 4,811,417 (Prince et al; Mar. 7, 1989), the disclosure of which is incorporated herein by reference, describes a form of bag stack in which an elongate vertical slit provides the support rod receiving aperture of each handle of the stack of bags and the handles are maintained in alignment in the stack by means of releasable heat welds holding the end of each handle to its neighbour in the stack.
U.S. Pat. No. 4,981,216 (Wilfong; Jan. 1, 1991), the disclosure of which is incorporated herein by reference, describes a further form in which a front part of the handle is detachable from the support rod to assist in opening the mouth of the first bag for loading.
The known systems suffer from various inherent disadvantages. The act of lifting the loaded first bag, forward and off the support rods, is itself awkward and potentially straining when performed repeatedly many times a day in a seated position. The use of aperture flaps which are permanently heat-sealed together is inconvenient in the act of loading a stack of bags onto the dispenser, and results in a block of redundant flaps, which must be discarded, as the stack is consumed. The use of a central block of mounting tabs from which the bags are detached, while serving to maintain the integrity of the stack before use, is wasteful of plastic, as the block is thrown away after the last bag of the stack has been used. Moreover, the webs connecting the bags to the block are prone to break as the block is being engaged onto the hook element of the dispenser, thereby causing the bags to "daisychain" or pull forward prematurely from the stack before the first bag has been removed, as described in our British Patent Application No. GB-A-2309957.
It is an aim of the present invention to go at least some way towards overcoming the disadvantages of the previously known systems, or at least to provide an acceptable alternative system.